Heat Transfer Project Zirconium Billet Temperature

1. Heat Transfer Project Zirconium Billet Temperature by Brent Staley and Brad Smith

2. Zirconium rods are used to house the fuel pellets in nuclear reactors Prior to extrusion, the billets must be lubricated to prevent sticking on the die The billets must be heated to a specific temperature for the lubricant to cure properly Background

3. Heat a Zirconium billet to a desired temperature in a barrel of water and measure the time Calculate time needed to achieve desired temperature and compare with measured time Objective

5. Assumptions: Infinite cylindrical shape assumed Temp. of the barrel wall equals temp. of the water Thermal properties are constant throughout the billet Spatial effects were considered Temp. of the water is constant throughout the barrel Calculations

6. Free Convection of Concentric Cylinder Calculations

7. Calculations

8. Experimental SetupPopcorn can - hold the waterPyrometer – measure the surface temperature of billetThermometer – measure temperature of the waterOverhead bridge with block of wood – lower the billet into waterHeat plate – heat water to desired temp.Stop watch – for obvious reasons

9. Temp. water – 180 F Starting temp. of billet – 78 F Final temp. of billet – 166 F Calculated time from 78 F to 166 F – 228 sec Measured time – 180 sec Difference of 48 sec Experimental results

10. The calculated time was 1.27 times longer than the measured time We can attribute this discrepancy to: - End effects of the billet - Interference of the pyrometer with water vapor - 1st order approximate assumption method is just that – an approximation Conclusions